Up to 70 years later, former North Catholic High School students are reporting that members of a religious order sexually abused them because they finally believe they can be believed, experts say.

“It's not likely people would have believed you 30, 40, 50 years ago,” said Tony Mannarino, a psychologist and co-director of the Center for Traumatic Stress in Children and Adolescents at Allegheny General Hospital in the North Side. “For people to whom this happened, they felt a lot of shame about what had happened.”

The Catholic Diocese of Pittsburgh on Wednesday confirmed the number of alleged victims has risen to 19 in what has become one of the largest sex abuse scandals in the diocese's history.

The Rev. Ron Lengwin, a spokesman for the diocese, said the accusers identified three more brothers of the Marianist order as having abused them. They are: James Kline, who taught at North Catholic from 1940 to 1947; Joseph Binder, who was there from 1961-66, 1975-76 and 1979-89; and Julius May, whose time is unknown. Kline died in 1997, Binder in 2000 and May in 1970.

The oldest allegation now dates to the 1940s, Lengwin said. Last week the diocese said the case involved 12 accusers and five brothers from the 1950s and '60s.

The Marianists, who run 19 high schools across the country, said they had no knowledge of any alleged abuse until reading media reports. The Rev. Martin Solma, provincial of the Marianist province based in St. Louis, said he felt “shame.”

“These things are done behind closed doors and secretly. We're also a victim. We feel violated by what these individuals have done, so everybody is a victim.”

“I don't know how you wouldn't know or would know,” Lengwin said. “A lot of people were able to hide their immoral behavior.”

Nicholas Cafardi, former dean of the law school at Duquesne University and author of a book of sex abuse in the Catholic Church, said the Marianist order should have been more aware.

“I think they completely violated their obligation to the diocese by not telling the diocese that these things had happened,” said Cafardi, who chaired the National Review Board for the Protection of Children and Young People of the U.S. Conference of Catholic Bishops.

The North Catholic scandal erupted March 20 when the diocese learned that Marianist Brother Bernard Hartman, 74, a former science teacher at North Catholic, is awaiting trial in Australia on charges that he molested four students at a Catholic school there in the 1970s and '80s.

Lengwin said the diocese reacted promptly, eventually sending two letters to North Catholic graduates that generated the reports of abuse.

The diocese and Marianists have offered free counseling. Beyond that, Solma said, the order will have to meet with its review board and follow its recommendations.

Carmen DiGiacomo, a 1959 graduate of the school, applauded the diocese's efforts to reach potential victims.

“They're trying to get to the bottom of this as quickly as possible,” he said.

In a prepared statement, David Clohessy, director of the Survivors Network of those Abused by Priests, said the diocese should do more.

“Pittsburgh's bishop should personally visit every single parish where a proven, admitted and credibly accused priest, nun, seminarian or church employee worked.”

Mike Manko, spokesman for the Allegheny County District's Attorney's Office, said it has no information to pursue a criminal case.

Lengwin has identified the rest of the brothers implicated as William Charles Hildenbrand, who was at North Catholic from 1951 to 1961; Francis Meder, who was there from 1952-67 and 1970-76; and Ralph August Mravintz, who was at the school from 1960-64. All are deceased.

The last, Brother John Keegan, left the religious community in 1962. Lengwin does not know whether Keegan is still alive.

North Catholic was renamed Cardinal Wuerl North Catholic High School in 2013. The Troy Hill building will close at the end of the school year, and the school will move to a new campus in Cranberry in the fall.